Standardized quotes

[EricRabil]

JavaScript allows you to define strings in one of three ways: double quotes, single quotes, and backticks (as of ECMAScript 6). Each of these lines creates a string and, in some cases, can be used interchangeably. The choice of how to define strings in a codebase is a stylistic one outside of template literals (which allow embedded of expressions to be interpreted). Many codebases require strings to be defined in a consistent manner, and we should follow suit. I think it's a good idea for us to standardize our quotes. @AppleBetas